What Are Construction Loans for Custom Homes?

A construction loan for a custom home lets you borrow funds that are released in stages as your build progresses, rather than receiving the full loan amount upfront.

Unlike a standard home loan where you receive the entire sum at settlement, construction finance is drawn down progressively. You receive funds when certain milestones are reached, such as slab completion or lock-up stage. During construction, you typically pay interest only on the amount drawn so far, not on the total loan amount. Once building is complete, the loan converts to a standard home loan with principal and interest repayments.

This structure exists because the property you're borrowing against doesn't exist yet. The lender releases funds as the asset increases in value, reducing their risk while giving you access to the capital you need at each stage of the build.

How Construction Finance Differs from a Standard Home Loan

Construction finance is released in instalments tied to building milestones, while a standard home loan provides the full amount at settlement.

Consider a buyer purchasing a finished home. They receive the full loan amount on settlement day, start repaying principal and interest immediately, and move in shortly after. Now consider someone building a custom home on land they already own. They might need $450,000 for the build, but they don't need that full amount on day one. The lender releases funds after the slab is poured, then again at frame stage, lock-up, fixing stage, and practical completion. Between each draw, the buyer pays interest only on what's been released, not the full $450,000.

Most lenders structure this as a construction to permanent loan, which means you don't need to reapply once the build is finished. The loan automatically converts to a standard variable or fixed rate home loan after practical completion.

Land and Construction Packages Versus Building on Land You Own

You can finance a custom home either by purchasing land and building in one transaction, or by building on land you already own.

A land and construction package involves buying a block and funding the build under a single loan structure. The lender assesses both the land purchase and the proposed build together. You settle on the land first, then construction draws begin once the building contract is signed and council approval is in place. This approach works well if you've found suitable land and have a registered builder ready to commence building within a set period from the disclosure date.

If you already own the land, the lender uses the land's current value as part of your equity. In this scenario, you're only borrowing for the construction component. The equity in your land reduces the loan amount needed and can improve your borrowing capacity. Some buyers who purchased land years ago find they have substantial equity, which means they may not need a 20% deposit in cash because the land value covers part of that requirement.

The Construction Draw Schedule and How Payments Work

Funds are released at specific stages of construction, typically after a progress inspection confirms each milestone is complete.

Most lenders follow a five-stage progressive drawdown. The schedule usually looks like this: base stage after the slab is poured, frame stage once the timber or steel frame is up, lock-up when the roof and external walls are complete, fixing stage when internal fitout is done, and final draw at practical completion. After each stage, your builder requests payment, the lender arranges a progress inspection, and once the inspector confirms the work is complete, the funds are released.

During construction, you only pay interest on the amount drawn so far. If $150,000 has been released after the first two stages, you're paying interest on $150,000, not the full loan amount. Some lenders charge a progressive drawing fee each time funds are released, typically between $200 and $400 per draw. These fees add up across five or six draws, so factor them into your budget when calculating settlement costs.

Fixed Price Building Contracts and Cost Plus Agreements

A fixed price building contract sets the total build cost upfront, while a cost plus contract charges actual costs plus a builder's margin.

Most lenders in Victoria will only approve construction finance for builds under a fixed price contract with a registered builder. This contract locks in the build cost, which means the lender knows exactly how much they're lending and the buyer isn't exposed to budget blowouts. The contract should include a clear progress payment schedule that aligns with the lender's draw stages.

Cost plus contracts are less common for owner-occupier custom homes, but they do exist. Under this arrangement, you pay the actual cost of materials and labour, plus a percentage to the builder. Lenders view these as higher risk because the final cost isn't fixed, which makes it harder to determine the loan amount and assess serviceability. If you're considering a cost plus contract, expect fewer lender options and potentially a higher deposit requirement.

Owner Builder Finance and What Lenders Require

Owner builder finance is available, but fewer lenders offer it and the deposit requirement is typically higher.

If you're planning to act as your own builder, you'll need an owner builder permit from the Victorian Building Authority. Lenders treat owner builder projects as higher risk because there's no registered builder providing warranty insurance. Most lenders who do approve owner builder finance require a minimum 20% to 30% deposit, and some will want evidence of construction experience or a detailed project plan showing how you'll manage sub-contractors.

In practice, we see fewer owner builder applications approved compared to builds under a registered builder. If your goal is to save money by managing the build yourself, factor in the higher deposit requirement and the possibility of a higher interest rate. For some buyers, the savings from acting as owner builder are offset by the additional equity needed upfront.

Interest Rate Options During and After Construction

You can choose a variable or fixed interest rate during construction, though most borrowers stay on a variable rate until the build is complete.

During the construction phase, you're making interest-only repayments on the drawn amount. Fixing the rate during construction is possible, but it's less common because you're not paying down the principal yet and the loan balance increases with each draw. Once construction is complete and the loan converts to principal and interest repayments, you have the option to fix part or all of the loan amount, split between variable and fixed, or remain fully variable.

Some buyers prefer to lock in a fixed rate once construction is finished, particularly if rates are rising or they want certainty around repayments. Others stay variable to retain flexibility for additional payments or future refinancing. The choice depends on your financial situation and how long you plan to hold the property.

Council Approval and Development Application Timelines

You need council approval before construction draws can begin, and obtaining this approval should happen before you apply for finance.

Lenders require a copy of your building permit and council-approved plans before they'll issue a formal loan approval for the construction component. If you're still waiting on a development application or there are delays with council plans, the lender can issue conditional approval, but funds won't be available until the permit is in hand. In some parts of Victoria, council approval can take several months, so start this process early.

Delays with council approval don't just hold up the build. They can also affect your finance if your loan approval expires before construction starts. Most construction loan approvals are valid for three to six months. If your builder can't commence within that window due to permit delays, you may need to reapply or extend the approval, which can mean reassessing your financial position under current lending criteria.

Renovation Finance for Extending or Rebuilding an Existing Home

Renovation finance works similarly to construction finance, with staged drawdowns tied to completed work, and is available for major extensions or rebuilds.

If you're knocking down an existing home and rebuilding, or adding a substantial second storey, lenders treat this as construction finance rather than a standard home improvement loan. You'll need a fixed price building contract, council approval, and a registered builder. The lender will arrange progress inspections just as they would for a new build, releasing funds at agreed stages.

The difference is that you may already have a mortgage on the property. In this case, the lender assesses your total borrowing, combining the existing mortgage with the new construction loan. Your equity in the property before the renovation can reduce the amount you need to borrow, but the lender will also consider whether you can service the higher loan amount once construction is complete and repayments switch to principal and interest.

What Happens If Your Build Goes Over Budget

If construction costs exceed the contracted amount, you'll need to cover the shortfall from your own funds unless the lender agrees to increase the loan.

A fixed price contract should protect you from cost blowouts, but variations happen. You might decide to upgrade fixtures, add a feature wall, or change the floor plan mid-build. Each variation increases the total cost. If the new total exceeds your approved loan amount, the lender will reassess whether they're willing to lend the additional funds. They'll look at your current serviceability, the value of the partly built property, and whether the variation is reasonable.

In some cases, buyers run out of funds during construction because they underestimated costs like landscaping, driveways, or connecting utilities. These items aren't always included in the building contract, but they're necessary before you can move in. Before you sign the contract, work through a detailed budget that includes everything from the slab to the letterbox, not just the builder's quote.

Applying for Construction Finance and What Documents You'll Need

You'll need to provide standard loan application documents plus construction-specific items like the building contract, council-approved plans, and a progress payment schedule.

The construction loan application process involves two stages. First, you apply for pre-approval based on your income, deposit, and borrowing capacity, just as you would for any home loan. Once you have a signed building contract and council approval, you return to the lender with those documents to activate the construction component. The lender reviews the contract to confirm the build cost, checks that progress payments align with their draw schedule, and arranges a valuation based on the completed home's projected value.

Lenders want to see that the finished property will be worth more than the total loan amount. If you're borrowing $500,000 for land and construction, the lender will expect the completed home to be valued at least at that amount, and ideally higher. If the valuation comes in lower than expected, you may need to increase your deposit or reduce the loan amount.

When to Speak to a Mortgage Broker About Construction Finance

Speak to a broker before you sign the building contract, not after.

Many buyers choose a builder, sign a contract, and then apply for finance, only to find the contract terms don't align with what lenders require or that they can't borrow the full amount. A conversation before you commit gives you a clear picture of how much you can borrow, which lenders will support your project, and whether the builder's payment schedule will work with the lender's draw stages.

We regularly work with clients building custom homes across Victoria, and the difference between a smooth approval and a stressful one usually comes down to timing. If you've already selected your land or builder, a broker can structure the finance around your plans. If you're still in the early stages, a broker can help you understand your borrowing capacity so you know what's possible before you commit.

Building a custom home is a significant financial and personal commitment. You're not just buying a property, you're creating something that reflects your needs and your vision. The finance structure should support that process, not complicate it. Call one of our team or book an appointment at a time that works for you.

Frequently Asked Questions